The method and apparatus of this invention are improvements upon the apparatus for tempering makeup air of my U.S. Pat. No. 4,124,021, which discloses a grease extraction ventilator which includes a water bath or water sprays into or through which are directed the air and other gases rising from cooking equipment. This water is pumped through a heat exchanger for a portion of incoming makeup air which is directed into the room, while the remainder of the makeup air is directed toward the intake of the ventilator, to reduce the amount of air withdrawn from the room by the suction blower. The heat exchanger may also be utilized at a desired location, within or outside of the room in which the ventilator is installed, to heat or cool air or other fluids for heating or other purposes. Makeup air is directed into the upper portion of the room, such as through a horizontal slot adjacent the ceiling. An air chamber opposite the ventilator has a front wall and a lower discharge outlet on the rear side, which directs makeup air toward the ventilator intake. To reduce an undesired flow of air from the lower edge of the front wall, which may produce a flow of smoke and the like into the room, an orifice adjacent the horizontal slot may direct makeup air downwardly along the front wall of the air chamber.
Haried U.S. Pat. No. 3,194,308, directed to a cross flow heat exchanger with ducts in the panel, discloses a heat exchanger through which is passed exhaust air from the drying apparatus of a dry cleaning establishment, to heat a heat transfer medium which is then circulated through another heat exchanger, through which makeup air for the dry cleaning establishment is passed. One example of the heat transfer medium is water which includes an anti-freeze.
Among the objects of this invention are to provide a novel method and apparatus for tempering makeup air through utilization of the heating or cooling effect of water contacted by air and products of cooking equipment, passed through a water contact means of a grease extraction ventilator; to provide such a method and apparatus by which the maximum effectiveness of the waste energy may be secured; to provide such a method and apparatus which may be essentially automatically controlled; to provide such a method and apparatus in which supplemental heat and cooling for extreme conditions may be provided; to provide such a method and apparatus which operates efficiently and effectively; and to provide such apparatus which may be constructed in a convenient and relatively economical manner.